Contact jaw element for the positive carbons of arc lamps



May 11, 1943. M. MOKIN 2,319,151

CONTACT JAW ELEMENT FOR THE POSITIVE CARBONS OF ARC LAMPS Filed Nov. 8, 1941 INVENTOR. MAXMOK/N BY Q2 5 ATTORNEY Patented May 11, 1943 CGNTACT JAVV ELEMENT FOR THE POSI- TIVE CARBONS OF ARC LAMPS Max Mokin, Brooklyn, N. Y.

Application November 8, 1941, Serial No. 418,304

1 Claim.

The invention relates to jaw means comprising two members between which are to be held for axial advance a carbon rod or the like as utilized in an arc lamp, more especially to the positive carbon jaw members with respect to which the carbon advances and rotates. As now provided, these members consist of a solid relatively heavy block or body portion of metal such as commercial copper or copper having small quantities of alloying materials combined therewith, a block being provided also with attaching means for securing the block in position on the lamp house burner frame. Corresponding halves of a cylindrical bearing are provided on respective blocks with the faces of the bearing halves being juxtaposed to receive the positive carbon rod which progresses gradually through the bearing as the active point of the rod burns away. Due to this travel of a rod through the bearing thus provided and to the electrical burning due to the high amperage employed as well as to the intense heat developed at the active point of a rod, the bearings in a relatively short period become so worn away that both of the entire jaw members must be discarded and replaced by construct the portion to be discarded of a more serviceable material so that not only is the contact block or member in service for a longer period, but when it becomes necessary to provide a new bearing for the carbon rod, the cost of replacement thereof is considerably reduced.

This is effected by constructing the two members constituting the jaw means for the axially advancing positive carbons of one portion which is of relative high electrical conductivity, such as of commercial copper, and constituting the main or body portion of the member, while the actual wear portion is an element of mass comparatively small with respect to that of said body portion and consists of a suitable alloy electrically conductive and afiording a more durable wearing surface. These two portions or elements of a contact jaw member are then arranged to be separably united so that when wear has progressed to a stage which would ordinarily require an entirely new block, it is necessary merely to remove the replaceable portion of a jaw and substitute a new one at comparatively little expense.

The nature of the invention, however, will best be understood when described in connection with the accompanying drawing, in which:

Fig. 1 is a perspective view of a pair of the novel jaw members assembled to receive the positive carbon of an arc lamp.

Fig. 2 is a front elevation of one of the members; and Fig. 3 is a plan thereof.

Fig. 4 is an end elevation of one of the jaw members with the separable element displaced from the body portion thereof; and Fig. 5 is a rear elevation thereof.

Fig. 6 is a horizontal section on the line 66, Fig. 2 of the drawing.

Referring to the drawing, more especially Fig. 1 thereof, wherein two contact jaw members are indicated as juxtaposed for receiving a positive carbon (not shown) of an arc lamp, for example, as utilized in the usual and well-known lamp house assembly, each jaw member comprises essentially an electrically highly-conductive body portion It for introduction of the operating current which is received through the supporting element H extending downwardly from the said body portion and integral therewith. Such body portion or element constitutes the major portion of the contact member and is of electrically highly-conductive metal such as commercial copper, while the other portion and replaceable element constitutes but a minor proportion of the total mass of the jaw member and may be of a suitable alloy to afford a more durable wearing surface though of somewhat reduced electrical conductivity. For example, the replaceable element I2 may be constituted of a suitable copper-nickel alloy, for example Monel metal.

As set forth, the two portions of the jaw member are designed to be rigidly secured together when the jaw means is in service; and the replaceable element affords a half of a cylindrical bearing l3 on its outer surface, the bearing being completed by juxtaposing corresponding halves of the two elements, as indicated in Fig. 1 of the drawing.

In order to effect the securing of the two jaw elements, as well as their separation when a replacement is to be made of the replaceable element l2, the body portion of an element I0 is bored through transversely at a number of points to provide the bores l5 and the companion replaceable element is tapped in the juxtaposed surface to provide the threaded openings 16 which are of lesser diameter than the diameter of the bores l5. Suitable bolts I! pass through the bores 15 and are threaded into the openings Hi to draw the two jaw elements together, a washer l1 being preferably inserted under the head of a bolt. To replace an element [2, it is then necessary merely to unscrew the bolts and release the element.

It is preferred, also, in order to insure a more perfect contact between the juxtaposed faces of the two jaw member elements, namely: the body portion and the replaceable portion, to insert a thin washer N3 of soft, highly conductive metal such as pure copper, the washer being perforated to pass the bolts H. An integral strap l9 may also be extended outwardly from the washer over the body portion and then turned under the head of one of the bolts.

I claim:

A contact jaw unit for the axially advancing positive carbon of an arc lamp, comprising a body portion having an integral part for introduction of the operating current to the body portion, and a replaceable jaw element of appreciably greater wearing properties than said body portion and of relatively small mass with respect thereto affording a complete bearing half for the carbon to contact the same and to transmit electric current substantially over one-half of its circumference, together with removable securing means passing through the body portion for rigidly holding the replaceable element to the said body portion, the respective bearing halves of two units being adapted for juxtaposition to enclose completely the carbon.

MAX MOKIN. 

